More than a decade ago, photographer Ed Freeman set out to capture the gay rights struggle in a photograph for the cover of Frontiers, a gay magazine. To do so, he relied on an image — the flag-raising at Iwo Jima — that has been imitated and adapted countless times since it was captured in the midst of one of America’s bloodiest battles.

The photograph was taken Feb. 23, 1945, four days into an operation that would rage for more than a month. Associated Press photographer Joe Rosenthal snapped the image as five Marines and a Navy corpsman raised an American flag on Mount Suribachi, the highest summit on the Pacific island. Within weeks, three of those Marines were killed in combat, putting them among the 6,821 American fatalities on Iwo Jima. An additional 19,000-plus U.S. troops were wounded, and more than 18,800 Japanese troops died.

Rosenthal’s photograph received a Pulitzer Prize, and became the centerpiece of a multi-billion dollar war bond effort. It also inspired the Marine Corps War Memorial, the equally iconic bronze monument at the entrance to Arlington National Cemetery that was erected in honor of all Marines killed in combat. In short, Rosenthal’s image became — and remains — a spiritual force.

Freeman found that out the hard way last week. More than a decade after his adaptation of the photograph was published, it circulated on social media following the Supreme Court’s decision Friday to allow same-sex marriage in all 50 states.

That prompted a backlash against Freeman — including a death threat he says he reported to the FBI.

“He said if he ever saw me, he’d kill me,” Freeman said in a phone interview. “I got swamped with vitriolic hate mail.”

Reaction on Twitter also included a lot of criticism:

Freeman, who is gay, also was blasted on Facebook after posting his gay pride Iwo Jima image along with a message saying it never occurred to him that it would “someday come to symbolize the victory we are celebrating today.”

When I took this picture almost ten years ago, it never, never occurred to me that it would someday come to symbolize the victory we are celebrating today. Congratulations to all of us! Love to you all.

Posted by Ed Freeman Photography on Friday, June 26, 2015

Many of the responses were heated.

“Im all for gay rights and equal for all but DO NOT DISRESPECT THOSE WHO SERVED, SACRIFICED, AND DIED FOR YOUR COUNTRY AND YOUR RIGHTS AND FREEDOM,” wrote one commentor in response. “Its this [expletive] that will drive ppl to hate on you. You WANT RESPECT THEN GIVE IT TO THOSE WHO DESERVE AND EARNED IT.”

Freeman, whose studio is in Los Angeles, said he never expected the backlash. The image, taken before social media was ubiquitous, was partially staged using models, and completed with Photoshop, he said.

“The principle complaint that people have is that I am equating the gay struggle with the contribution and sacrifice of American servicemen,” he said. “But there is no equal sign here. This is not meant as a sign of disrespect. For God sake, no. I totally support people in uniform. There is no comparison going on here. The comparison is going on in people’s heads, and they’re spoiling for a fight. They’re already on edge because of  the gay marriage decision.”

Freeman said that before social media, his version of the image would only have been seen by people who wanted to view it, not “straight people from small towns in Idaho.” The Iwo Jima photo “is one of the greatest pictures ever,” and has been duplicated to do everything from sell Ol’ Glory beer to promote the Hard Rock Cafe, he noted.

Outrage about the adaptation of Rosenthal’s image is nothing new, however. In 2008, for example, Time magazine came under heavy criticism for publishing a cover in which the American flag in it was swapped for a tree for a global warming-themed issue.

More recently, the British Airlines Stewards and Stewardesses Association (BASSA) union came under fire in 2010 for adapting the Iwo Jima image to show stewardesses raising a union flag, and Under Armour apologized this year for adapting it for a T-shirt in which athletes are shown raising a basketball hoop. The shirt was removed from stores, and company officials said in a tweet that “we deeply regret and apologize the release of a shirt that is not reflective of our commitment to support & honor our country’s heroes.”

Freeman said there is “no way in hell” that he meant his adaptation of the Iwo Jima image to be provocative.

“This picture was just a flashpoint for a lot people who are looking for a reason to lash out, so I guess I get to be the whipping boy,” he said. “I’m fine with that if that’s what it takes.”

Tongue in cheek, Freeman said one critic already has given him another idea.

“One of them said, ‘Well, why don’t you have an astronaut planting a gay flag on the moon?'” he laughed. “And I said, ‘Well, why not?'”